/Engine/Source/Runtime/Core/Public/Math/TransformNonVectorized.h
Rotation is accumulated additively, in the shortest direction (Rotation = Rotation +/- DeltaAtom.Rotation * Weight) Translation is accumulated additively (Translation += DeltaAtom.Translation * Weight) Scale3D is accumulated additively (Scale3D += DeltaAtom.Scale3D * Weight)
void AccumulateWithShortestRotation ( const [TTransform](API\Runtime\Core\Math\TTransform)< T > & DeltaAtom, [FReal](API\Runtime\Core\Math\TTransform\FReal) BlendWeight )